Filter elements, air cleaner assemblies, and methods of use and assembly

ABSTRACT

Air cleaner assemblies, components therefor, and features thereof are described. Also described are methods of assembly and use. In depicted examples, the air cleaner assemblies and components optionally use advantageous housing seal features. Methods of assembly and use are described.

RELATED APPLICATIONS

This application is being filed on Dec. 1, 2017, as a PCT InternationalPatent application and claims priority to U.S. Provisional patentapplication Ser. No. 62/428,913, filed Dec. 1, 2016, and U.S.Provisional patent application Ser. No. 62/463,263, filed Feb. 24, 2017,the entire disclosures of which are incorporated by reference in theirentirety.

FIELD OF THE DISCLOSURE

The present disclosure relates to filter assemblies, for example aircleaner assemblies, and components and features thereof, and methods ofassembly and use. The filter assemblies comprise a housing having aremovable and replaceable filter cartridge therein. Various features offilter housings and/or the cartridges are described, which can providefor advantage. Methods of assembly and use are described.

BACKGROUND

Air or other gas filtering is desirable in a number of systems. Atypical application is in the filtration of intake air to internalcombustion engines. Another is in the filtration of crankcaseventilation filter assemblies. Typically, such systems comprise filterassemblies having a serviceable filter cartridge therein. After a periodof use, filter media within a filter housing requires servicing, eitherthrough cleaning or complete replacement. Typically, for an air cleaneror crankcase ventilation filter assembly used with an internalcombustion engine, for example on a vehicle, the filter media iscontained in a removable and replaceable, i.e. serviceable, component,typically referred as a filter element or cartridge. The filtercartridge is configured to be removably sealed within the air cleaner,in use. Improvements in filter arrangements relating to assembly,serviceability, use are desirable. The filter cartridge can be providedas a primary filter cartridge or a secondary filter cartridge. The aircleaner assembly can contain only a primary filter cartridge or both aprimary filter cartridge and a secondary filter cartridge.

SUMMARY

Filter assemblies (such as air cleaner assemblies or crankcaseventilation filter assemblies) components therefor; and, featuresthereof are described. Also described are methods of assembly and use.The filter assemblies generally comprise a housing having a filtercartridge removably positioned therein.

An example assembly includes a first filter cartridge and a secondfilter cartridge, wherein the first filter cartridge has a first sealingstructure configured for sealing against a portion of a housing andhaving a sealing surface, and wherein the second filter cartridge has asecond sealing structure configured for sealing against the first filtercartridge sealing surface. In one embodiment, the first sealingstructure is an outwardly directed radial seal while the second sealingstructure is an inwardly directed radial seal. Another example assemblyincludes a first filter cartridge having filtration media defining aninterior space with an open end cap at one end and having a sealingstructure that is located entirely within the interior space and spacedfrom the open end cap. In one embodiment, the sealing structure is anoutwardly directed radial seal. Another example assembly includes aremovable seal surface component installed onto a portion of thehousing, wherein a first filter cartridge has a first sealing structurethat seals against an interior portion of the removable seal surfacecomponent, and wherein a second filter cartridge has a second sealingstructure that seals against an outward portion of the removable sealsurface component.

There is no specific requirement that an air cleaner assembly, componenttherefor, or feature thereof include all of the detail characterizedherein, to obtain some advantage according to the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an air cleaner assembly including ahousing assembly with at least one filter cartridge installed thereinaccording to the present disclosure.

FIG. 2 is a top view of the air cleaner assembly shown in FIG. 1.

FIG. 3 is an exploded view of the air cleaner assembly shown in FIG. 1,wherein a first filter cartridge, a second filter cartridge, and aserviceable seal surface component are shown as being utilized inconjunction with the housing assembly.

FIG. 4 is a cross-sectional view of the air cleaner assembly of FIG. 1,taken along the line 4-4 in FIG. 2, with the components shown in FIG. 3installed within the housing assembly.

FIG. 4A is an enlarged cross-sectional view of a portion of the aircleaner assembly shown in FIG. 4, as indicated at FIG. 4.

FIG. 5 is a cross-sectional view similar to FIG. 4, but with the housingassembly not being shown.

FIG. 6 is a perspective view of the serviceable seal surface componentshown in FIG. 3.

FIG. 7 is a cross-sectional view of the serviceable seal surfacecomponent shown in FIG. 7.

FIG. 8 is a cross-sectional view of the second filter cartridge shown inFIG. 3.

FIG. 9 is a cross-sectional view of the first filter cartridge shown inFIG. 3.

FIG. 10 is an exploded view of the air cleaner assembly shown in FIG. 1,wherein a second example of a first filter cartridge is shown as beingutilized in conjunction with the housing assembly.

FIG. 11 is a cross-sectional view of the air cleaner assembly of FIG. 1,taken along the line 4-4 in FIG. 2, with the components shown in FIG. 10installed within the housing assembly.

FIG. 11A is an enlarged cross-sectional view of a portion of the aircleaner assembly shown in FIG. 11, as indicated at FIG. 11.

FIG. 12 is a cross-sectional view similar to FIG. 11, but with thehousing assembly not being shown.

FIG. 13 is a cross-sectional view of the first filter cartridge shown inFIG. 10.

FIG. 14 is an exploded view of the air cleaner assembly shown in FIG. 1,wherein a third example of a first filter cartridge and a second exampleof a second filter cartridge are shown as being utilized in conjunctionwith the housing assembly.

FIG. 15 is a cross-sectional view of the air cleaner assembly of FIG. 1,taken along the line 4-4 in FIG. 2, with the components shown in FIG. 14installed within the housing assembly.

FIG. 15A is an enlarged cross-sectional view of a portion of the aircleaner assembly shown in FIG. 15, as indicated at FIG. 15.

FIG. 16 is a cross-sectional view similar to FIG. 15, but with thehousing assembly not being shown.

FIG. 17 is a cross-sectional view of the second filter cartridge shownin FIG. 14.

FIG. 18 is a cross-sectional view of the first filter cartridge shown inFIG. 14.

FIG. 19 is a cross-sectional view of the air cleaner assembly shown inFIG. 1, wherein the second example of a first filter cartridge and athird example of a second filter cartridge are shown.

FIG. 20 is an enlarged cross-sectional view of a portion of the aircleaner assembly shown in FIG. 19.

FIG. 21 is a cross-sectional view of the air cleaner assembly shown inFIG. 1, wherein the first example of a first filter cartridge and afourth example of a second filter cartridge are shown.

FIG. 22 is an enlarged cross-sectional view of a portion of the aircleaner assembly shown in FIG. 21.

DETAILED DESCRIPTION

Herein, example filter assemblies, filter cartridges, features andcomponents therefor are described and depicted. A variety of specificfeatures and components are characterized in detail. Many can be appliedto provide advantage. There is no specific requirement that the variousindividual features and components be applied in an overall assemblywith all of the features and characteristics described, however, inorder to provide for some benefit in accord with the present disclosure.

It is noted that a plurality of embodiments are depicted and described.The embodiments are not meant to be exclusive with respect to featuresdepicted. That is, selected features of one embodiment can be applied inone or more of the other embodiments if desired, to advantage. In manyexamples, the filter assembly depicted is an air cleaner assembly, forexample, used to filter intake air for an internal combustion engine.However, the concepts disclosed are not in any way limited to such anapplication and may be applied across a variety of differentapplications, such as crankcase ventilation. The disclosed filterassemblies are generally “gas filter assemblies,” since the carrierstage being filtered is gas (air or crankcase ventilation gases). Whilethe techniques described herein will typically be used in applicationfor gas filtration, they can be used in the filtration of othermaterials, for example, liquids, if desired.

I. Filter Assembly—General Description

The reference numeral 1, FIG. 1, generally indicates a filter assembly,for example an air cleaner or air cleaner assembly or arrangement inaccord with the present disclosure. The filter assembly (in the examplean air cleaner assembly) 1 comprises a housing 2. The housing 2 definesa sidewall 2 s and includes: a first body or housing section 3; and asecond body section or access cover 4. In the example depicted, theaccess cover 4 is removably secured to the first body section 3, butalternatives are possible. Also although alternatives are possible, forthe example depicted, attachment of the cover section 4 to the bodysection 3 is by a latch arrangement 5 including over center latches. Thecover section 4 can alternatively be held to the body section 3 by atwist lock arrangement. An exemplary twist lock arrangement is depictedin U.S. application Ser. No. 15/192,272, filed on Jun. 24, 2016, thedisclosure of which is incorporated herein by reference.

In general, the air (gas) cleaner 1 includes an air (gas) flow inletarrangement 7. In the example depicted, the air flow inlet arrangement 7is an inlet tube indicated at 7 t, on the body section 3. The particularinlet tube 7 t depicted, is configured as a side, tangential, inlet,i.e. gas flow is directed tangentially against an inner wall of housing2, as opposed to being directed directly toward a housing central axisX. Alternate inlet arrangements, locations and direction are possible.However, the tangential inlet arrangement depicted is convenient andadvantageous for reasons discussed below.

At 8, a dust/water ejector arrangement is depicted on the housing 2,comprising tube 9. In the example depicted, the tube 9 comprises aportion of access cover 4, although alternatives are possible. The tube9 is covered by an evacuator valve arrangement 10, in the exampledepicted comprising a duck-billed valve of a type widely used with aircleaners, see for example WO 2006/06241 A1; U.S. Pat. Nos. 6,419,718 B1;and 8,864,866, incorporated herein by reference. Alternate evacuatorvalve arrangements can be used.

At 15, an outlet tube or flow tube is depicted, as a portion of housing2 positioned on a remainder of the housing body section 3. The tube 15can be formed integral with the housing body 3, but the outlet tube 15can be a separate piece snap-fit or otherwise attached to the housingbody 3.

In operation, air (gas) to be filtered enters the air cleaner assemblythrough inlet tube 7 t. Eventually the air/gas passes through filtermedia of a filter cartridge arrangement positioned within interior 2 iof the housing 2. After passage through media of the filter cartridge,the filtered air is directed to exit the housing through outlet tube 15.From outlet tube 15, the filtered air is directed to downstreamequipment such as to a turbo system or to the air intake of an enginesystem.

The particular air cleaner (filter) assembly 1 depicted includes anoptional precleaner stage. The precleaner stage is provided in part bydirecting air from inlet tube 7 t tangentially into interior 2 i of thehousing 2. The air will then be directed into a cyclonic pattern aroundan interior of the assembly 1. This will tend to drive a portion of anywater or dust particles contained within the air stream, against aninterior surface of sidewall 2 s. This material, separated from the airstream, will eventually migrate to, and enter, the tube 9, from whichejection occurs through valve 10.

The particular air cleaner assembly 1 depicted is configured so that itcan be mounted in a variety of orientations, for example with thecentral axis X directed vertically, or alternatively with the centralaxis X directed horizontally.

The housing body section 3 can include a mounting pad arrangementthereon. The mounting pad arrangement can be formed integral with aremainder of the housing 2 or it can be a separate piece. The mountingpad arrangement is used to help secure the housing 2 in place, onequipment with which air cleaner 1 would be used. By having the mountingpad arrangement on the housing section 3, the housing section 3 can beretained in place on the equipment by bolts, or other systems duringservicing, with access cover 4 being removably secured to body section3, for convenient servicing. An exemplary mounting pad arrangement thatcan be used as part of the housing section 3 is disclosed in U.S. Pat.No. 8,864,866, the disclosure of which is incorporated herein byreference.

As thus far described the air cleaner assembly is similar to many priorair cleaner assemblies, including those depicted and described in WO2006/06241 A1; WO 2009014988; U.S. Pat. Nos. 6,419,718 B1; and,8,864,866, the disclosures of which are incorporated herein byreference.

Reference is now made to FIGS. 3 and 4, which show the housing assemblyof FIGS. 1 and 2 used in conjunction with a first example of serviceableinternal filtration components that can be provided within the housing2. In the exploded view of FIG. 3, filter cartridge 25, filter cartridge27, and serviceable seal surface component 17 are viewable and shown asbeing positionable within housing interior 2 i. Alternative serviceablecomponent arrangements which utilize the same housing 2 are shown atFIGS. 10 to 13 and at FIGS. 14 to 18. The variations of filter cartridge25 will be described in greater detail below. In general, the cartridge25 is a serviceable component that includes an extension of filter media26 through which air to be filtered passes, before it can exit assembly1. In addition, the variations of filter cartridge 27 will be describedin greater detail below. In general, the cartridge 27 is a serviceablecomponent that includes an extension of filter media 28 through whichair to be filtered passes before it exits assembly 1. The filtercartridge 25 can be referred to as a primary filter cartridge or primaryfilter element, and the filter cartridge 27 can be referred to as asecondary or safety filter cartridge or secondary or safety filterelement. The serviceable seal surface component 17, which is present inonly the first embodiment at FIGS. 3 to 9, will also be described ingreater detail below.

By the term “serviceable component” as used herein, and in reference tothe cartridges 25 and 27 and seal surface component 17, it is meant thatthe seal surface component 17 and cartridges 25, 27 are removable andreplaceable in the air cleaner assembly 1. Thus, as the media 26 and/or28 occludes during use, the cartridge 25 and/or the cartridge 27 can beremoved, and can be refurbished or replaced. Similarly, as the sealsurface component 17 becomes worn, damaged, or otherwise unsuitable foruse, the seal surface component 17 can be removed, and can berefurbished or replaced.

Referring to FIG. 2, it can be seen that housing 2 includes an optional,but advantageous, shield arrangement 29 surrounding a selected portionof the filter cartridge 25. The shield arrangement 29 includes firstshield section 30 in housing body section 3, oriented to surround aportion of the cartridge 25 at that location, creating an annulus 31between the shield 30 and outer sidewall 32. Air from inlet 7 isdirected into inlet aperture 7 a and into annulus 31, and in a cyclonicpattern. Shield 30 inhibits direct impingement, of the dust and othermaterial carried by the inlet air in annulus 31, and onto the media 26until after the air has moved at least partially through the cyclonicpattern and past shield 30 in a direction toward access cover 4.

In FIG. 4, at 33 a second shield section of shield arrangement 29 isdepicted in access cover 4. The second shield section 33 defines anannulus 34 between the shield 33 and sidewall 35 of section 4. As shownat FIG. 1, an egress or outlet aperture is located in the sidewall 2from housing interior 2 i to interior 9 i of tube 9. The egress oroutlet aperture 37 is in communication with the annulus 34. The shield33 helps facilitate removal of dust and other materials through aperture37 into dust ejector arrangement 8.

Use of shield arrangements analogous to shield arrangement 29, with oneor more shields analogous to sections 30 and 33, is common in many aircleaner arrangements, see for example WO 2006/06241 A1; WO 2009/014988;U.S. Ser. Nos. 61/446,653; 61/473,296; 6,419,718 B1; and 8,864,866, thedisclosures of which are incorporated herein by reference. Analogousfeatures and principles can be used here.

It is noted that the use of the shield arrangement 29 and dust ejectorarrangement 8 is consistent with many applications in which a “dualstage” or “two stage” air (gas) cleaner is desired, having a firstprecleaner stage to separate water and larger particles from the airbefore it passes into the filter cartridge 25 (the second stage).However, such features are generally optional, and many of theprinciples of the present disclosure can be applied in air cleaners thatdo not have such a two stage configuration or precleaner stage.Downstream of the filter cartridge 25 is the secondary filter cartridge27 so that air passes through both of the filter cartridge 25 and thefilter cartridge 27 prior to exiting via the air outlet 15. It should beunderstood that the air cleaner assembly 1 can be operated with thefilter cartridge 25 alone, with the filter cartridge 27 alone, or withboth the filter cartridge 25 and the filter cartridge 27 providedtogether and as shown in FIG. 2.

II. Filter Assembly—First Filter Arrangement Embodiment

As indicated above, many of the features previously identified anddiscussed with respect to FIGS. 1-2 relating to general air cleanerconfiguration (filter assembly) and operation are well known features,forms of which have been used in a variety of systems. Certain uniquecharacteristics of the present air cleaner, of FIGS. 1-2 and 3-9, relateto the inclusion of the serviceable seal surface component 17. Theserviceable seal surface component 17 provides seal surfaces againstwhich the filter cartridges 25, 27 can be sealed. As the component 17 isserviceable, a new sealing surface can be provided in the assembly atany point in time, for example, when wear or damage to the component 17occurs or when damage to an originally provided permanent seal surface(e.g. filter cartridge baffle 114) on the housing 2 becomes worn ordamaged. In this section, selected features relating to the serviceableseal surface component 17 are discussed.

As most easily seen at FIGS. 6 and 7, the serviceable seal surfacecomponent 17 includes a main body 17 a (e.g., ring or annular-shaped)extending from a first end 17 b to a second end 17 c. Between the firstend 17 b and the second end 17 c, the main body 17 a includes a firstextension segment 17 d and a generally parallel second extension segment17 e joined by a connecting portion 17 f. The first and second extensionsegments 17 d, 17 e are spaced apart such that an annulus 17 g is formedtherebetween. The second extension part 17 e is further joined to a sealstructure 17 h which defines a channel 17 i into which a seal member 17j is received. In one aspect, the main body 17 a of the component 17includes an inwardly stepped portion 17 p. The inwardly stepped portion17 p can act as a stop against which the end of the filter cartridge 27can rest.

As presented, the main body 17 a is an integrally formed unit having allof the aforementioned components 17 b-17 i with the exception of theseal member 17 j. In the example shown, the seal member 17 j is aseparate O-ring. However, in an alternative arrangement, the seal member17 j can also be integrally formed as a portion of the main body 17 a.Additionally, the first and second extensions 17 d, 17 e themselves mayprovide the sealing surfaces. The main body 17 a may be formed from avariety of materials, such as an injection molded polymeric material.

In one aspect, the first extension part 17 d defines an outer sealingsurface 17 k and an inner sealing surface 17 m while the secondextension part 17 e defines an inner sealing surface 17 n and an outersealing surface 17 o. When the serviceable seal surface component 17 isinstalled into the housing 2, a filter cartridge baffle 114 of thehousing 2 is received into the annulus 17 g formed between the first andsecond extension parts 17 d, 17 e until, for example, contact is madebetween an end 114 a of the filter cartridge baffle 114 or between thesecond end 17 c of the main body 17 a and a surface of the housing 2. Asconfigured, the filter cartridge baffle 114 is a portion of the outlettube 15 that extends into the interior volume 2 i of the housing 2. Oncethe component 17 is fully inserted, the component surface 17 m faces anouter surface 114 c of the baffle 114 while the component surface 17 ofaces an inner surface 114 b of the baffle 114. In this position, and asmost easily seen at FIG. 4A, the seal member 17 j forms a seal againstthe inner surface 114 b of the filter cartridge baffle 114. This sealformed between the seal member 17 j and the filter cartridge baffle 114ensures that a continuous seal will exist between the filter cartridgebaffle 114 and any component sealed to the serviceable seal surfacecomponent 17.

In some applications, the surfaces 114 b and 114 c of the filtercartridge baffle 114 initially serve as the sealing surfaces againstwhich the filter cartridges 25, 27 form a seal. Over time, one or bothof these surfaces may become worn or damaged. In such cases, theserviceable seal surface component 17 can be mounted onto the filtercartridge baffle 114 to provide new seal surfaces 17 n, 17 k. As theseal member 17 j is located proximate the second end 17 c of the mainbody 17 a and adjacent to the seal surface 17 n, the seal member 17 jdoes not interfere with a seal between the component 17 and a filtercartridge 27. It may also be useful to install the serviceable sealsurface component 17 in instances where it is desired to provide afilter cartridge 25 or 27 having seals that are sized or shapedincompatibly with the filter cartridge baffle 114.

The filter cartridge 25 can be referred to as a primary filter cartridgeor as a primary filter element, and the filter cartridge 27 can bereferred to as a secondary or safety filter cartridge or as a secondaryor safety element. In general, the primary filter cartridge or primaryfilter element and the secondary or safety filter cartridge or thesecondary or safety filter element can be referred to as the filtercartridge or the filter element for convenience. Based on context, itshould be apparent that references being made to the primary filtercartridge or the secondary filter cartridge.

In general terms, again, the cartridges 25 and 27 are serviceablecomponents. That is, they can be removed and replaced through thelifetime of the air cleaner 1, just as described for the serviceableseal surface component 17. A releasable seal is needed between thecartridge 25 and the serviceable seal surface component 17, and betweenthe cartridge 27 and the component 17, to allow the cartridges to beserviceable components and to ensure that unfiltered air does not bypassthe cartridge 25 and/or the cartridge 27 and enter the outlet tube 15,as this can cause damage to the engine.

The filter cartridge 25 generally includes filtration media 26 extendingbetween first and second opposite media ends 41 and 42. First media end41 is engaged by a first end cap or piece 45. The second media end 42 isengaged by a second end cap or piece 46. Thus, the media 26 extendsbetween opposite end caps (or end pieces) 45, 46.

Although alternatives are possible with selected techniques describedherein, for the example depicted, the filter media 26 is configuredsurrounding an open filter interior 26 i, generally around a centralaxis X of the air cleaner 1 and cartridge 25. The media 26 can bepleated media, although alternatives are possible. The media 26 can beconfigured in a cylindrical pattern as shown, if desired, althoughalternatives are possible. For example, the media 26 can be somewhatconical in extension between the opposite ends 41, 42. Also, the mediacan be configured with non-circular inner and/or outer perimeters; forexample oval or other cross-sectional configurations are possible. Inaddition, the primary filter cartridge 25 can be provided with a screenor support structure 26 s extending from the first end 41 to the second42 to help support the filtration media 26 while allowing gas (air) topass therethrough. The filtration media 26 can be embedded in the firstand second end caps 45 and 66. In addition, the screen or supportstructure 26 s for the filtration media 26 can be embedded in the firstand second end caps 45 and 46.

Although alternatives are possible with selected techniques describedherein, the second end piece or cap 46 is typically a closed end pieceor cap, extending completely across the media 26 at the second end 42,closing that end 42 of the media 26 and the filter interior 26 i. Thatis, end piece or cap 46, for the example depicted, is a closed end pieceor cap, i.e. an end cap having no aperture therethrough in communicationwith the open filter interior 26 i.

First end piece or cap 45 on the other hand, is an open end piece orcap. That is, it surrounds and defines a central aperture 50 incommunication with the media, in the example via open filter interior 26i. In typical use, aperture 50 is an air flow exit aperture from themedia, for example open filter interior 26 i, for filtered air. Inalternate applications with a reverse direction of gas flow duringfiltering, aperture 50 can be an inlet aperture. In general, it is a gasflow aperture.

For the example depicted, first end piece 45 extends completely acrossall media 26 of the cartridge 25, from an outer perimeter 26 x to aninner perimeter 26 o. The first end piece 45 typically has only one,central, aperture 50 therethrough.

Again, when the access cover 4 is removed from the housing body section3, access to interior 2 i is provided for either installation or removalof the cartridge 25. The filter cartridge 25, then, needs to beadequately removably sealed to the serviceable seal surface component 17to protect against flow of unfiltered air into the exit tube 15. Toprovide for this, the cartridge 25 is provided with a primary (orhousing) seal arrangement 55.

With respect to the first housing seal or primary seal arrangement 55,and other features of first end cap 45, attention is directed to FIGS.4, 4A, and 9. The primary seal arrangement 55 can be seen as defining aradially directed seal or seal surface 55 s directed to engage thesurface 17 k of the serviceable seal surface component 17, forreleasable sealing. Accordingly, the primary seal arrangement 55 formsan inwardly directed radial seal with the serviceable seal surfacecomponent 17 when the primary filter cartridge 25 is installed in thefilter assembly 1.

Still referring to FIGS. 4, 4A, and 9, it will be understood that thesurface 55 s, of primary seal arrangement 55, that forms a seal withcomponent 17 is generally a radially directed surface. Hence, theprimary seal arrangement 55 can be referred to as a radially directedseal. By “radially” in this context, it is meant that the seal or sealsurface (and the compression of the seal surface during sealing) isdirected generally toward or away from (i.e. around) central axis X. Theparticular surface 55 s in the example depicted, is radially inwardlydirected relative to the central axis X, so the seal arrangement 55 canbe characterized as “radially inwardly directed.” It is noted however,that a radially outwardly directed seal can be used with some principlesin accord with the present disclosure.

It is noted that in the example depicted, the housing seal arrangement55 comprises a portion of end cap 45. In more general terms, the housingseal arrangement is mounted on a filter cartridge and is configured toreleaseably seal to a housing or component 17, whether that particularhousing seal arrangement comprises a portion of an end piece or not.

The preferred and advantageous housing seal arrangements describedherein are generally “non-clamp” or “clampless” housing sealarrangements. By this it is meant that they are established as thecartridge is inserted into the housing, without the need for tighteningthe clamp or connector of some type.

In one aspect, the end cap 45 and seal arrangement 55 can be constructedin a manner so that the amount of radial compression of end piece (cap)material in a region between surface 55 s and the support 62 will have amaximum compression of at least 10%, typically at least 15%, preferablyno more than about 40% and will typically be with a maximum compressionwithin the range of about 20-40%, inclusive. In some implementations, acompression between 30-40% is useful. To accomplish this, a seal supportcan be provided within the end cap 45.

Now referring to the filter cartridge 27 depicted in FIGS. 4, 4A, and 8.The filter cartridge 27 can be referred to a secondary filter element oras a safety filter element. During the servicing of the filter assembly1, wherein the primary filter cartridge 25 is removed and replaced witha new or refurbished filter cartridge, the secondary filter element 27prevents dust or debris from entering into the outlet tube 15.Furthermore, in the event of a malfunction in the primary filtercartridge 25, the secondary filter cartridge 27 is available to preventdust or debris from entering the outlet tube 15.

The secondary filter cartridge 27 includes a first end 80, and secondend 82, and filtration media 28 extending between the first end 80 andthe second end 82. In the exemplary secondary filter cartridge 27depicted, the first end 80 includes a first endcap 84 and the second end82 includes a second end cap 86. The secondary filter cartridge 27 canbe provided, if desired, without a second end cap 86. That is, thesecondary filter cartridge 27 can be provided so that the media extendsover the second end 82. In addition, the secondary filter cartridge 27can be provided with a screen or support structure 90 extending from thefirst end 80 to the second 82 to help support the filtration media 28while allowing gas (air) to pass therethrough. The filtration media 28can be embedded in the first and second end caps 84 and 86. In addition,the screen or support structure 90 for the filtration media 28 can beembedded in the first and second end caps 84 and 86.

The secondary filter cartridge 27 can be constructed so that thefiltration media 28 is configured surrounding an open filter interior 28i. The media 28 can be provided as depth media, although alternativesare possible. For example, the media 28 can be provided as pleated mediaor as multilayer laminate media such as the media disclosed in PCTPublication No. WO 2015/010085, the entire disclosure of which isincorporated herein by reference. In addition, the media 28 can beprovided as the filtration media layer arranged in a wave configurationdisclosed in PCT Publication No. WO 2015/010085. The media 28 can beconfigured in a cylindrical pattern as shown, if desired, althoughalternatives are possible. For example, the media 28 can be somewhatconical in extension between the opposite ends 80, 82. In addition, themedia can be configured with non-circular inner and/or outer perimeters.For example, the media can be configured having an oval, circular, orother cross-sectional configuration.

The second end cap 86 can be provided as a closed end piece or cap,extending completely across the media 28 at the second end 82, closingthe second end 82 of the filtration media 28 of the filter interior 28i. An exemplary top view of the second end cap 86 is shown, for example,in FIG. 8. The second end cap 86 can include projections 86 p that helpprovide separation and cushioning between the secondary filter cartridge27 and the primary filter cartridge 25. Furthermore, the second end cap86 can include a plurality of radially extending ridges.

The second end piece or cap 86 can be characterized as a closed endpiece or cap, i.e. an end cap having no aperture therethrough incommunication with the open filter interior 28 i. In various alternativeconfigurations, the second end 82 can be provided without an end cap. Inone variation of the secondary filter element 27 without a second endcap 86, the filtration media 28 extends over and encloses the second end82. That is, the filtration media 28 can form the closure at the secondend 82 thereby preventing unfiltered air from entering into the openfilter interior 28 i. In an alternative, the second end 82 can beprovided with a seal arrangement that mounts onto a secondary filterelement support structure wherein the support structure includes aclosed end corresponding to the second end 82 of the secondary filtercartridge 27. A remaining portion of the support structure would be opento flow of gas (air) therethrough. However, the closed end of thesupport structure would, in combination with the seal at the second endof the secondary filter cartridge 27 prevent unfiltered air fromentering into the open filter 28 i.

The first end cap 84 includes a support 92 and a secondary seal member94. The support 92 can be provided as part of the screen or supportstructure 90 or the support 92 can be provided as a separate componentsuch as a plastic preform. As shown in FIG. 8, the support 92 is part ofthe screen 90. That is, the screen 90 extends into the secondary sealmember 94 a sufficient amount to help support the secondary seal member94 when provided in a sealing relationship with the housing 2. Thecombination of the screen 90 (or support 92) and the secondary sealmember 94 forms the first end cap 84. The support 92 helps support thesecondary seal member 94 when it engages the serviceable seal supportstructure 17. The secondary seal member 94 can be referred to as ahousing seal structure or arrangement for the secondary filter cartridge27. In general, the secondary seal member 94 can be molded onto thesupport 92 and provides an outwardly directed sealing surface 96,directed to engage the surface 17 n of the separate seal surfacecomponent 17, for releasable sealing. When molded, the secondary sealmember 94 can be provided having an outer section 94 o on the outside ofthe support 92 and having an inner section 94 i on the inside of thesupport 92. In addition, the secondary seal member 94 can include aportion 94 t extending over a tip of the preform 92. The secondary sealmember 94 extends in a perimeter around a central open volume 15 i. Thecentral open volume 94 i can be in communication with the open filterinterior 28 i. During operation of the filter assembly 1 when thesecondary filter cartridge 27 is installed, air passes through thefiltration media 28 into the open filter interior 28 i, and then passesthrough the central open volume 94 i and into the outlet tube 15.

The secondary seal member 94 can be characterized as having an axialdistance or height 94 h from the bottom 94 b to the top 94 a that issufficient to provide a seal with the serviceable sealing surfacecomponent 17. As most easily seen at FIGS. 4, 4A, and 5, the secondaryseal member sealing surface 96 of the end cap 94 forms a seal with theinner sealing surface 17 n of the second extension part 17 e of theserviceable seal surface component 17.

III. Filter Assembly—Second Filter Arrangement Embodiment

Referring to FIGS. 10 to 13, a second filter arrangement 101 is shownthat can be utilized with the housing 2 depicted in FIGS. 1 to 4. Asmany of the features for this embodiment are similar to the thosepreviously discussed for the first embodiment, the description for thefirst embodiment is incorporated into this description for the secondembodiment. Where similar features do exist, similar reference numberswill be used, although in some instances a “100” series number will beused for the components of the second filter arrangement 101 (e.g. 125for filter cartridge instead of 25). The following description will belimited to the differences of the second embodiment over the firstembodiment. The primary difference is that that the second embodiment isnot shown as including a safety filter cartridge 27 or a serviceablesealing surface component 17 and the main filter cartridge 125 of thesecond embodiment is configured with a remote sealing structure 155 thatenables the main filter cartridge to seal to the inside surface 114 b ofthe filter cartridge baffle 114, even though, as shown, the cartridge ispositioned primarily to the outside of baffle 114.

Similar to the filter cartridge 25, the filter cartridge 125 is shownwith pleated media 126 forming an interior area 126 i and extendingbetween a first end 141 and a second end 142, wherein an open end cap145 is provided at the first end 141 and a closed end cap 146 isprovided at the second end 142. However, in this embodiment, the openend cap 145 is not provided with a seal structure or arrangement.Instead, a remote seal structure 155 is provided that is spaced inwardlyfrom the open end cap 145 and that is disposed entirely within theinterior area 126 i. As shown, the seal structure 155 defines a radiallyoutward directed sealing surface 155 s at a diameter D155 which is lessthan an internal diameter D145 of an interior surface 145 a of the openend cap 145. Accordingly, an annulus 157 is formed between the open endcap 145 and the seal structure 155. Taken together, the end cap 145, theseal structure 155, and the interconnecting extension member 152,discussed in detail below, can be collectively referred to as a sealarrangement 150.

The seal structure 155 is supported by an extension member 152. Theextension member 152 extends between a first end 152 a and a second end152 b, wherein the first end 152 a can be embedded within the open endcap 145 and the second end can be embedded in the seal structure 155.The seal structure may be alternatively constructed to utilize an O-ringor an overmolded construction. As shown, the extension member 152includes a first segment 152 c extending from the first end 152 atowards the closed end cap 146 and a second segment 152 d extending fromthe second end 152 b toward the closed end cap 146 in a spaced apart,parallel relationship with the first segment 152 c. The first and secondsegments 152 c, 152 d are joined by a segment 152 e, the length of whichdetermines the dimension of the resulting annulus 152 f between thefirst and second segments 152 c, 152 d. In one aspect, the length H152 cof the first segment 152 c is less than the length H152 d of the secondsegment such that the end face 155 a seal structure 155 is axiallyspaced or recessed from the end face 145 c of the open end cap 145 by adistance D1. In such a configuration, the seal structure 155 can becharacterized as being fully within the interior area 126 i defined bythe media 126.

The seal structure 155 can be made from a similar material as the endcap 145, such as a polyurethane material or an injection moldedpolymeric material. The extension member 152 can be formed from avariety of materials, for example polymeric and metal materials. In oneexample, the end cap 145, the extension member 152, and the sealstructure 155 are integrally formed as a single component.

Referring to FIGS. 11 to 12, the installation of the filter cartridge125 is shown as being installed within the housing 2. As shown, thefilter cartridge baffle 114 associated with the outlet tube 15 isreceived within the annulus 152 e between the first and second segments152 c, 152 d of the extension member 152. The end cap 145 can beprovided with a dimension and configuration such that the inner andouter radial surfaces 145 a, 145 b of the end cap seal against thefilter cartridge baffle 114 and housing 2, respectively. The end cap 145can also be provided with a dimension and configuration such that noradial seal is formed with the filter cartridge baffle 114 and/or thehousing 2. As the filter cartridge 125 is received into the housing 2,the seal structure 155 is received into the filter cartridge baffle 114and the filter cartridge 125 will eventually reach its installedposition in which the end face 145 c of the end cap 145 is brought intocontact with the housing 2. In this position, the seal surface 155 scompresses against the interior surface 114 b of the filter cartridgebaffle 114 to form a seal. As such, a sealed airflow path between theinlet 7 and outlet tube 15 is achieved such that all air flowing out ofthe outlet tube 15 must first pass through the filter cartridge 125.This configuration is advantageous in instances where the housing mayhave been originally designed for use with a safety filter element and amain filter element that initially sealed directly against the filtercartridge baffle 114, but where the outer surface 114 c of the filtercartridge baffle 114 is no longer suitable for providing a sealingsurface in cases of excessive damage or wear. Accordingly, the filtercartridge 125 can be utilized to extend the useful life of a filterassembly.

IV. Filter Assembly—Third Filter Arrangement Embodiment

Referring to FIGS. 14 to 18, a third filter arrangement is shown thatcan be utilized with the housing 2 depicted in FIGS. 1 to 4. As many ofthe features for this embodiment are similar to the those previouslydiscussed for the first and second embodiments, the description forthose embodiments is incorporated into this description for the secondembodiment. Where similar features do exist, similar reference numberswill be used, although in some instances a “200” series number will beused for the components of the third filter arrangement 201 (e.g. 225for filter cartridge instead of 25 or 125). The following descriptionwill be limited to the differences of the second embodiment over thefirst embodiment. The third embodiment is similar to the secondembodiment in that the main filter element is provided with a sealstructure that is remote from the end cap and within the interior spaceof the media. However, the third embodiment is different from theprevious embodiments in that the secondary or safety filter cartridge isprovided with a sealing surface against which the sealing structure ofthe main filter cartridge can be sealed. With such an arrangement, theouter surface 114 c of the filter cartridge baffle 114 or another partof the housing 2 is not relied upon for forming a seal with the mainfilter cartridge. Thus, the third embodiment is advantageous incircumstances where the outer surface 114 c may be worn or damaged orwhere the sealing interface with the housing 2 is work, damaged, or notcompatible with the main filter element end cap and seal structure. Inan alternative construction, the filter cartridge 225 is provided with ashorter length such that the seal structure extends axially away fromthe open end cap and is not disposed within the interior space of themedia.

With reference to FIGS. 14-18, it can be seen that filter cartridge 225is similar in construction to the filter cartridge 125 in that a sealstructure 255 is provided that is remote from the end cap 245 and thatis within the interior area 226 i of the media 226. The filter cartridge225 is shown with pleated media 226 forming an interior area 226 i andextending between a first end 241 and a second end 242, wherein an openend cap 245 is provided at the first end 241 and a closed end cap 246 isprovided at the second end 242.

In contrast to the filter cartridge 125, filter cartridge 225 has a sealstructure 255 having an inwardly directed radial sealing surface 255 s.As mentioned previously, the remote seal structure 255 is provided suchthat it is spaced inwardly from the open end cap 245 and such that isdisposed entirely within the interior area 126 i. As shown, the sealstructure 155 defines a radially inward directed sealing surface 255 sat a diameter D255 that is less than an internal diameter of the end cap245.

The seal structure 255 is supported by an extension member 252. Takentogether, the end cap 245, the seal structure 255, and theinterconnecting extension member 252 can be collectively referred to asa seal arrangement 250. As shown, the extension member 252 extendsbetween a first end 252 a and a second end 252 b, wherein the first end252 a is embedded within or a part of the open end cap 245 and thesecond end is embedded in or attached to the seal structure 255. Asshown, the extension member 252 includes a first segment 252 c extendingfrom the first end 152 a towards the closed end cap 246 and a secondsegment 252 d extending from the second end 252 b toward the closed endcap 246 in a spaced apart, parallel relationship with the first segment252 c. The first and second segments 152 c, 152 d are joined by asegment 252 e. In one aspect, the length H252 c of the first segment 252c is greater than the length H252 d of the second segment such that theend face 255 a seal structure 255 is recessed from the end face 245 c ofthe open end cap 245 by a distance D2. In such a configuration, the sealstructure 255 can be characterized as being fully within the interiorarea 226 i defined by the media 226.

The seal structure 255 can be made from a similar material as the endcap 245, such as a polyurethane material or an injection moldedpolymeric material. The extension member 252 can be formed from avariety of materials, for example polymeric and metal materials. In oneexample, the end cap 245, the extension member 252, and the sealstructure 255 are integrally formed as a single component.

Referring to FIG. 17, the safety filter cartridge 227 is shown. Thesafety filter cartridge 227 is similar to filter cartridge 27 in thatmedia 228 and support structure 290 are provided that extend between afirst end 280 and a second end 282, wherein a closed end cap 286 isprovided at the second end 282 and an open end cap 284 is provided atthe first end 280. The first end cap 284 includes a support 292 and asecondary seal member 294 having an outwardly directed radial sealsurface 296. As mentioned previously, the support 292 can be formed bythe support structure 290. When molded, the secondary seal member 294can be provided having an outer section 294 o on the outside of thesupport 292 and having an inner section 294 i on the inside of thesupport 292. The secondary seal member 294 can be characterized ashaving an axial distance or height 294 h from the bottom 294 b to thetop 294 a that is sufficient to provide a seal with the filter cartridgebaffle 114.

The safety filter cartridge 227 is also provided with an annular sealsurface extension member 217. As shown, the extension member 217 extendsbetween a first end 217 a and a second end 218 b and has a height H217that is greater than or equal to the height H242 c of the first segment252 c of the extension member 252. However, if the second segment 252 dhas a sufficient length, then the height of the extension member 217 canbe shorter than the first segment 252 c. As shown, the first end 217 ais embedded in the first end cap 284 and surrounds the filter media 290.The extension member can be impervious to gas (e.g. air) passagetherethrough. The extension member 217 is provided with a continuousouter surface 217 s extending between the first and second ends 217 a,217 b. The continuous outer surface 217 s provides a sealing surfaceagainst which the sealing surface 255 s of the main filter cartridgeseal structure 255 can form a seal. The extension member 217 can beformed from a polymeric material, such as ABS plastic. The extensionmember 217 can also be formed as an integral portion of the supportstructure 290. In one alternative design, the safety filter media, endcap 286, and support structure 290 are not provided, and the sealstructure 284 and the extension member 217 are provided together as aremovable seal surface component.

The installed filter cartridges 225, 227 can be seen at FIGS. 15 and15A. In these figures, it can be seen that the filter cartridge 227 isinstalled such that the outer surface 294 o of the open end cap 284forms an outwardly directed radial seal against the inner surface 114 bof the filter cartridge baffle 114. Once the safety filter cartridge 227has been installed in this position, the main filter cartridge 225 canbe installed such that the safety filter cartridge 227 is receivedwithin the interior area 226 i of the main filter cartridge 225. The endcap 245 can be provided with a dimension and configuration such that theinner and/or outer radial surfaces 245 a, 245 b of the end cap 245 sealagainst the filter cartridge baffle 114 and housing 2, respectively. Theend cap 245 can also be provided with a dimension and configuration suchthat no seal radial seal is formed with the filter cartridge baffle 114and/or the housing 2.

As the filter cartridge 225 is received into the housing 2, the sealstructure 255 will pass over the seal surface extension member 217 onthe safety filter cartridge as the filter cartridge 225 eventuallyreaches its installed position at which point the end face 245 c of theend cap 245 is brought into contact with the housing 2. Other optionsfor axial position or constraint of the filter cartridge 225 can also beutilized. As configured the internal diameter D255 of the seal surface255 s is less than the external diameter D217 of the seal surface 217 s.Accordingly, the seal structure 255 compresses against and forms aninwardly directed radial seal against the extension member outer surface217 s. Once fully installed, the safety filter cartridge 227 forms aseal with the filter cartridge baffle 114 and the main filter cartridgeforms a seal with the safety filter cartridge 225, thus ensuring a cleanair flow path between the inlet 7 and outlet 17 of the housing 2. Thisconfiguration is advantageous in instances where the outer surface 114 cof the filter cartridge baffle is excessively worn or damaged and/orinstances where a main filter cartridge 225 end cap is not compatiblefor sealing within the housing 2 at some other location.

V. Filter Assembly—Fourth Filter Arrangement Embodiment

Referring to FIGS. 19-20, a fourth filter arrangement 301 is shown thatcan be utilized with the housing 2 depicted in FIGS. 1 to 4. The fourthfilter arrangement 301 is most similar to the second filter arrangement101 as each utilizes the same filter cartridge 125. Accordingly,features of the filter cartridge 125 and its installation within housing2 need not be further described here. However, in contrast to the secondfilter arrangement 101, the fourth filter arrangement 301 additionallyincludes a safety filter cartridge 327. The safety filter cartridge 327is generally similar in design to the safety filter cartridge 27, but issized to form a radially outwardly directed seal against the secondsegment 152 d of the extension member 152 associated with the filtercartridge 125.

Similar to filter cartridge 27, the second filter cartridge 327 hasmedia 328 and a support structure 390 that extend between a first end380 and a second end 382, wherein an open end cap 384 is provided at thefirst end and a closed end cap 386 is provided at the second end 382.The open end cap 384 includes a seal support 392 over which a sealmember 394 is disposed. Variations in construction described for filtercartridge 27 are applicable for second filter cartridge 327 and need notbe discussed further here.

In one aspect, the seal member 394 of the open end cap 384 includes aradially outwardly directed seal surface 396. As can be most easily seenat FIG. 20, the seal surface 396 forms a seal against the second segment152 d of the extension member 12 associated with the filter cartridge125. As configured, the seal member 394 is provided with an outsidediameter D396 that is slightly greater than an inside diameter D152 dsuch that a slight interference fit exists. Due to the compressibilityof the seal member 394, the seal member 394 will conform to diameterD152 d when the filter cartridge 327 is installed within the filtercartridge 125.

In order to install the filter cartridges 125, 327 within the housing 2,the filter cartridge 125 is first installed into the interior space 126i of the filter cartridge 327. This is accomplished by coaxiallyaligning the filter cartridges 125, 327 and then inserting the closedend cap 386 of the filter cartridge 327 through the opening defined bythe remote seal structure 155 extending from the open end cap 145 of thefilter cartridge 125. Insertion in this direction continues until theclosed end cap 386 of the filter cartridge 327 is brought into contactwith the interior surface 146 s of the closed end cap 146 of the filtercartridge 125. At this installation location, the overall length of thefilter cartridge 327 is such that the seal surface 396 is axiallyaligned with the second segment 152 d of the extension member 152 of thefilter cartridge 152. Other alignment methods for ensuring that the sealsurface 394 is axially aligned with the second segment 152 can be alsobe used. For example, the extension member 152, or another part of thefilter cartridge 125, can include a stop member against which a portion(e.g. the seal member 394) of the filter cartridge 327 engages. Once thefilter cartridge 327 has been installed within the filter cartridge 125,the cartridges can then be installed together within the housing 2.Insertion of the combined filter cartridge assembly 125, 327 isperformed such that the seal surface 155 s of the remote seal structure155 associated with the filter cartridge 125 is sealed against thefilter cartridge baffle 114 of the housing 2, as previously described inrelation to the filter cartridge 125 in Section III above.

VI. Filter Assembly—Fifth Filter Arrangement Embodiment

Referring to FIGS. 21-22, a fifth filter arrangement 401 is shown thatcan be utilized with the housing 2 depicted in FIGS. 1 to 4. The fourthfilter arrangement 301 is most similar to the first filter arrangement 1as each utilizes the same filter cartridge 25. Accordingly, features ofthe filter cartridge 25 and its installation within housing 2 need notbe further described here. However, in contrast to the first filterarrangement 1, the fifth filter arrangement 401 combines the safetyfilter cartridge 27 and a modified version of the seal surface component17 into a single assembly 427.

Similar to filter cartridge 27, the filter cartridge 427 has media 428and a support structure 490 that extend between a first end 480 and asecond end 482, wherein an open end cap 484 is provided at the first endand a closed end cap 486 is provided at the second end 482. The open endcap 484 includes a seal support 492 over which a seal member 494 isdisposed. Variations in construction described for filter cartridge 27are applicable for second filter cartridge 427 and need not be discussedfurther here.

In one aspect, the open end cap 484 additionally includes a seal surfacecomponent 117 having a main body 117 a (e.g., ring or annular-shaped)extending from a first end 117 b to a second end 117 c. Between thefirst end 117 b and the second end 117 c, the main body 117 a includes afirst extension segment 117 d and a generally parallel second extensionsegment 117 e joined by a connecting portion 117 f. The first and secondextension segments 117 d, 117 e are spaced apart such that an annulus117 g is formed therebetween. As shown, the second extension segment 117e is adjacent the media 128 and/or support structure 190 and is embeddedwithin the material forming the seal support 492. In one aspect, thefirst extension part 117 d defines an outer sealing surface 117 k. Inone example, the seal surface component 117 is formed from a materialthat has a greater hardness than the material used to form the sealsurface component 117. In one example, the seal surface component 117and the open end cap 484 are formed from a similar material. In oneexample, the seal surface component 117 and the open end cap 484 areunitarily formed (e.g. via molding) as a single component. In oneexample, the seal surface component 117 is formed in an independentmolding process. In one example, open end cap 484 is simultaneouslymolded onto the support structure 90, the media 428, and the sealsurface component 117.

When the filter cartridge 427 is installed into the housing 2, thefilter cartridge baffle 114 of the housing 2 is received into theannulus 117 g formed between the first and second extension parts 117 d,117 e until the end of the open end cap 484 bottoms out against asurface of the housing 2. Once the filter cartridge 427 is fullyinserted, a seal surface 484 s of the open end cap 484 seals against theinner surface 114 b of the filter cartridge baffle 114. After filtercartridge 427 is installed, the filter cartridge 25 can be inserted intothe housing 2 in the same manner as previously described in Section IIabove. Upon insertion, the seal surface 55 s associated with the openend cap 45 of filter cartridge 25 seals against the outer sealingsurface 117 k of the seal surface component 117.

VII. Filtration Media and Terminology

The particular material chosen for the media is a matter of choice for aselected application. When the filter assembly is an air cleaner, any ofa variety of media materials now used in air cleaners can be used withprinciples according to the present disclosure.

The media pack can comprise only media 26, 126, 226 or the media can beprovided with an inner and/or outer liner before installation in thecartridge 25, 125, 225. The media can be pleated, nonpleated, depthmedia, or wave media although additional alternatives are possible. Themedia can be provided in a variety of configurations includingcylindrical and conical, and with a variety of inner and/or outerperimeter definitions, for example circular or oval. Additionally,fluted filter media (media having media ridges) can be used to providefluid filter constructions in a variety of manners. One well knownmanner is characterized herein as a z-filter construction. The term“z-filter construction” as used herein, is meant to include (but not belimited) a type of filter construction in which individual ones ofcorrugated, folded or otherwise formed filter flutes are used to define(typically in combination with facing media) sets of longitudinal,typically parallel, inlet and outlet filter flutes for fluid flowthrough the media. Some examples of z-filter media are provided in U.S.Pat. Nos. 5,820,646; 5,772,883; 5,902,364; 5,792,247; 5,895,574;6,210,469; 6,190,432; 6,350,296; 6,179,890; 6,235,195; Des. 399,944;Des. 428,128; Des. 396,098; Des. 398,046; and, Des. 437,401; each ofthese cited references being incorporated herein by reference.

It is noted that although the seal of the arrangements are sometimescharacterized as “radial.” However, as a result of the non-circularshape, some of the sealing forces will be directed other thanspecifically at or away from the central axis X of the cartridge. Theseals are nevertheless characterized herein as “radial,” since, ingeneral, the seal surfaces on the cartridge and housing are generallyradially directed and the sealing forces are either radially outwardlydirected or radially inwardly directed, around the axis X, depending onwhether an outwardly or inwardly directed seal surface is involved.Alternately stated, the compression forces are still not axial (i.e. inthe longitudinal direction of axis X), but rather are generally radial.There are applications, however, where the seal forces are not aligneddirectly toward or away from the axis X in each of these non-circularconfigurations.

In more general terms, radial seals comprise seal surfaces thatsurrounds (directed toward away from) a central axis. That central axisin many instances will comprise a central axis of a filter cartridgearound which media is also positioned. However, from alternativearrangements described herein below, it will be understood that a radialseal can be a seal that surrounds an axis that is not also a centralaxis for the cartridge (by contrast, an axial seal is a seal that isgenerally aligned with a central axis around which the seal ispositioned, typically also, but not necessarily in all instances, acentral cartridge axis X).

In the general terminology used herein, the various housing sealarrangements depicted can also be characterized as generally comprisinga radially directed seal surface, since the seal direction for thevarious housing seals depicted in the drawings, is generally with asurface of the seal engaging some portion of the housing (be it aportion of an outlet tube or outer portion of the housing, depending onwhether which of the two of the housing seals is involved) that can begenerally characterized as a “radially directed surface.” In eachinstance, the surface that actually forms the seal is directed around(and facing toward or away from) a central axis X (typically, also ofthe cartridge)as opposed to an axial seal which would be generally withseal forces directed in the longitudinal direction of the central axisX. The examples depicted are “radial” seals or “radially” directed sealsmeaning that the surface of the seal member on the cartridge that willform a seal in engagement with a housing or replaceable sealing surface,is directed either towards or away from a central axis of the cartridge,as opposed to being orthogonal to the axis. In some examples shown, theseals are “outward” radial seal surfaces or “outwardly” directed radialseals since the actual surface of the seal member on the cartridge thatwill form a seal is generally directed away from a central axis of thecartridge, as opposed as to toward the axis. In some examples shown, theseals are “inward” radial seal surfaces or “inwardly directed” radialseals since the actual surface of the seal member on the cartridge thatwill form a seal that is generally directed towards a central axis ofthe cartridge, as opposed to away from the axis. However, many of theprinciples described herein can be applied in alternate arrangements inwhich the seal surface on the cartridge that engages the housing to forma seal is directed radially toward the central axis.

The radial housing seals described herein can be generally characterizedas “non-clamp,” “non-clamping” or “clampless” arrangements or by similarterms. By this it is meant that the seal arrangements typically do notinvolve the use of a clamp such as a hose clamp or other structure thatneeds to be tightened in order to provide for a secure seal. Rather, theseals are established by mere installation, with compression of the sealmaterial against a surface of the housing being directed by a cartridgecomponent.

The principles described herein can be applied in a variety of filterassemblies. Examples described in which the principles applied to (air)gas filter assemblies. Examples are described include gas/air filtersand crankcase ventilation filter assemblies. The principles can beapplied to a variety of alternate gas filtration arrangements, in someinstances even with liquid filter assemblies.

Principles according to the present disclosure relate to interactionsbetween filter cartridges and air cleaner systems, in advantageousmanners to achieve certain, selected, desired results discussed below.The filter cartridge would generally include a filter media therein,through which air and other gases pass, during a filtering operation.The media can be of a variety of types and configurations, and can bemade from using a variety of materials. For example, pleated mediaarrangements can be used in cartridges according to the principles ofthe present disclosure, as discussed below.

In this section, examples of some media arrangements that are usablewith the techniques described herein are provided. It will beunderstood, however, that a variety of alternate media types can beused. The choice of media type is generally one of preference for:availability; function in a given situation of application, ease ofmanufacturability, etc. and the choice is not necessarily specificallyrelated to the overall function of selected ones of various filtercartridge/air cleaner interaction features characterized herein.

Listing of claims:
 1. A filter cartridge comprising: a. filtration mediadefining an interior area and extending between a first end and a secondend; b. an open end cap coupled to the filtration media at the firstend, the open end cap having an end face; and c. a seal structure havingan end face and an outwardly directed radial sealing surface, whereinthe seal structure is located entirely within the filtration mediainterior area such that the seal structure end face is axially spacedfrom the open end cap end face.
 2. The filter cartridge of claim 1,wherein the seal structure is connected to the open end cap by anextension member.
 3. The filter cartridge of claim 1, wherein the sealstructure is formed from the same material as the open end cap.
 4. Thefilter cartridge of claim 2, wherein the seal structure, extensionmember, and open end cap are integrally formed as a singular component.5. The filter cartridge of claim 1, further including a support framelocated within the interior space, the support frame being configured tosupport the filtration media.
 6. The filter cartridge of claim 1,wherein the seal structure is formed from a polyurethane material. 7.The filter cartridge of claim 5, wherein the seal structure extends fromthe support frame. 8.-18. (canceled)
 19. A filter assembly comprising:a. a housing defining an interior cavity extending between an inlet andan outlet; b. a safety filter cartridge installed within the housing,the safety filter cartridge being sealed against a portion of thehousing such that air passing from the inlet to the outlet must passthrough filtration media of the safety filter cartridge; and c. a mainfilter cartridge installed within the housing, the main filter cartridgebeing sealed against a portion of the safety filter cartridge such thatair passing from the inlet to the outlet must additionally pass throughfiltration media of the main filter cartridge.
 20. The filter assemblyof claim 19, wherein the safety filter cartridge includes an annularsealing member circumscribing at least a portion of the safety filtercartridge filtration media, and wherein the main filter cartridge formsa seal against the annular sealing member.
 21. The filter cartridgeassembly of claim 20, wherein the safety filter cartridge includes anopen end cap and wherein the annular sealing member is partiallyembedded within the open end cap.
 22. The filter assembly of claim 20,wherein the main filter cartridge includes a seal structure that sealsagainst the annular sealing member.
 23. The filter assembly of claim 21,wherein the main filter cartridge filtration media defines an interiorspace, and wherein the seal structure is located entirely within theinterior space.
 24. The filter assembly of claim 20, wherein the sealstructure defines an inwardly directed radial seal.
 25. The filterassembly of claim 22, wherein the seal structure is connected to themain filter cartridge open end cap by an annular extension member.
 26. Aserviceable filter sealing component for a filter assembly comprising:a. an annular main body extending between a first end and a second end,the main body including a first extension member, a second extensionmember, and a third extension member, the first and second extensionmembers being arranged in a spaced apart parallel relationship with thethird extension member connecting the first extension member to thesecond extension member, wherein the first, second, and third extensionmembers together define an annulus for receiving an annular component ofa housing of the filter assembly; and b. a seal structure locatedproximate the main body first end, the seal structure being configuredfor sealing against the filter assembly housing part, wherein the sealstructure extends at least partially across the main body annulus. 27.The serviceable filter sealing component of claim 26, wherein the mainbody defines a channel for receiving the seal structure.
 28. Theserviceable filter sealing component of claim 27, wherein the sealstructure is formed as an O-ring.
 29. The serviceable filter sealingcomponent of claim 26, wherein the seal structure is integrally formedwith the main body.
 30. The serviceable filter sealing component ofclaim 26, wherein the main body further defines an inwardly steppedportion adjacent the seal structure.
 31. The serviceable filter sealingcomponent of claim 26, wherein the second extension member is radiallyoutward of the first extension member. 32.-38. (canceled)